1. Field of the Invention
The present invention relates generally to electrical circuits, and more particularly but not exclusively to battery chargers.
2. Description of the Background Art
Battery chargers may be used to charge batteries of portable electrical devices including cell phones, power tools, digital cameras, MP3 players, and personal digital assistants, to name a few examples. A battery charger may be implemented using a commercially-available PWM (pulse width modulation) controller integrated circuit (IC), such as the FAN102 primary-side-regulated (PSR) PWM controller from Fairchild Semiconductor. When employed in a battery charger, a PWM controller IC is configured to compensate for voltage drop on a charging cable connecting the battery charger to the battery. In a conventional PWM controller, such as the FAN 102 controller, the cable voltage drop necessitates the use of a dedicated cable compensation circuit and an extra, dedicated IC pin to attach additional electrical components for cable compensation to meet particular application specifications, such as output current, output voltage, and cable resistance.